Percutaneous Cryoablation for Renal Cell Carcinoma

Overall and disease-free survival was nearly 100% after a median follow-up of one year, study shows.

SAN DIEGO—Percutaneous cryoablation for renal cell carcinoma is a safe modality that carries extremely high success rates after up to 2.5 years of follow-up, according to researchers.

They say their data support the notion that interventional cryoablation should be a first-line treatment option for patients for whom surgery is not an option presenting with renal tumors 4 cm in diameter or smaller.

“Non-surgical patients or patients with limited renal function now have a chance for cure, assuming the cancer is small and limited to the kidney, without affecting their renal function,” said lead investigator Christos Georgiades, MD, PhD, assistant professor of radiology at Johns Hopkins School of Medicine in Baltimore.

The treatment was effective for 100% of tumors 4 cm or smaller and 98% of tumors up to 7 cm, Dr. Georgiades reported here at the Society of Interventional Radiology's 34th Annual Scientific Meeting.

He and his colleagues have found that this treatment was effective 100% of time in tumors that were 4 cc or smaller, and approximately 98% in tumors that were up to 7 cc.

Over a period of 2.5 years, the researchers treated 73 renal cell carcinoma tumors in 68 consecutive patients (37 men, 31 women; median age 67 years) using CT-guided, percutaneous cryoablation. Biopsies were performed prior to the procedures. A treatment cycle consisted of a 10-minute freeze, an eight-minute thaw, and a 10-minute refreeze.

“This news is especially significant for individuals with small tumors, since more than 75% of patients who are diagnosed with kidney cancer have tumors that are 4 cm or less in size,” Dr. Georgiades said. “Patients who are not surgical candidates could have their tumors treated effectively without surgery, with quicker recovery, and mostly on an outpatient basis.”

The procedure was considered a technical success if the “ice-ball” extended at least 4 mm beyond the tumor margins. The follow-up protocol included of clinic visits and contrast-enhanced CT or MRI at three, six, and 12 months, and then annually thereafter.

The technical success rate was 100%. After a median follow-up of 12 months, overall and disease-specific survival was 97% and 98%, respectively. Among patients who had a median follow-up of two years, there was no evidence of cancer. No patient with disease confined to the kidney developed metastatic disease during follow up.

“The reason we have been successful is because have a very close collaborative effort between interventional radiology and urology,” Dr. Georgiades said. “This cannot work if one of the two is missing.”